Post-depositional mobility of platinum, iridium and rhenium in marine sediments
Article Abstract:
The high levels of platinum-group-elements (PGEs) found in some sediments may have resulted from prolonged distributive processes that are part of diagenesis rather than from meteoric impact. Some scientists have postulated that the elevated concentrations of iridium, platinum, rhenium and other PGEs at the Cretaceous/Tertiary boundary and at other boundaries in the geological record were caused by meteors striking the Earth. However, geochemical analysis of abyssal marine sediments indicates that redox processes may have produced the high concentrations at some of these boundaries.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
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Stratified prokaryote network in the oxic-anoxic transition of a deep-sea halocline
Article Abstract:
The Bannock brine lake-seawater interface is revealed to be a deep-sea microbial oasis. It consists of a biomass-dense, metabolically active microbial ecosystem that receives methane from the hypersaline brine below and organic particulates sedimenting through the water column from above, recycles this organic matter and interconverts diverse ionic species, which are used and reused as electron acceptors and donors.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2006
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Variability of the North Atlantic thermohaline circulation during the last interglacial period
Article Abstract:
Natural climate variability studies are used to evaluate future evolution. Ice cores in Greenland indicated that the Holocene period has been stable for 9,000 years. High-resolution ocean sediment records from the Bermuda Rise, covering the last interglacial period, are presented. Deep-water chemical changes appear to coincide with changes in surface climate.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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